It is not uncommon at entrance ways to commercial and industrial establishments to provide grates or like structures with scraping units, brushes or the like for removing soil from the soles of the shoes of entrants to the establishment. Door mats of various types are widely used for domestic and commercial establishments to assist in removing soil from the shoes of residents or customers. All such systems are designed primarily to limit the extent of the contamination of the shoes of the user passing beyond the assembly and generally work best with dry soil. However, frequently it is desirable to remove finer contaminants, dust or moisture from the soles of the shoes of a user and in such cases it is not uncommon to provide a cloth or paper web on top of the grate or mat so that the user, by rubbing his or her shoes upon this web, can remove traces of contaminants which might otherwise remain adherent. The web can also be moistened, if desired, to improve the cleaning operation.
However, the application of a cloth or paper overlay for a grate or mat of the type described has had the drawback that the fabric tends to wrinkle up and move on the grate or mat and that paper web tends to shift or crease to the point that the mat or grate may be uncovered and the cleaning surface available for the soles of the shoes may be reduced.